The IUCN/SSC Shark Specialist Group
Shark News 4: July 1995
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Status of the largetooth sawfish
Pristis perotteti Muller and Henle, 1841
Compiled by Sid Cook, Leonard Compagno and Madeline Oetinger
Taxonomy
The largetooth [southern] sawfish is one of three to eight species of
large to gigantic sawfishes in the genus Pristis which, with the
monotypic Anoxypristis cuspidata (Latham) [knifetooth sawfish],
comprise the Family Pristidae. The holotype was collected from
freshwater in Senegal, West Africa. As with other species of this genus
the taxonomy has been chaotic with a complex history of problems
exacerbated by lack of adult specimens in collections, questioned
identifications and a plethora of synonymies, which remain to be fully
resolved. At the present time there is considerable difficulty determining
how many valid species actually exist. For the purpose of this account
we assign P. zephyreus [eastern Pacific] as a junior synonym for P.
perotteti. Likewise we group this species into the P. pristis species
complex along with P. microdon, a species from which P. perotteti
may possibly prove not to be distinct (Compagno and Cook, in press).
Largetooth sawfish. Artist: Sid F. Cook.
©1991 by M.I. Oetinger. All rights reserved.
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Distribution and ecology
This is a relatively common (in a historical context),
large-bodied euryhaline sawfish of the warm-
temperate/tropical (>18°C to at least 30°C) eastern
Pacific [from Mazatlan, Mexico to Guayaquil,
Ecuador] and Atlantic Oceans [from northern
Texas and Florida to Brazil (West
Atlantic) and Gibraltar, Spain to
Angola, south-west Africa (East
Atlantic), also possibly the
Mediterranean Sea]. It is widely
but disjunctly distributed, being
strictly confined to shallow
(<10 m) nearshore marine,
brackish and freshwater (river/
lake) environments (Bigelow and
Schroeder, 1953). Though not
precisely known, it probably
spends most of its time near or on
the bottom. However, it is also
commonly observed in the wild and
in public aquaria swimming quite near
the surface for extended periods of time.
In the Pacific it is reported from freshwater in the Tuyra, Culebra,
Tilapa, Chucunaque, and Bayeno Rivers and at the Balboa and
Miraflores locks in the Panama Canal, Panama; the Rio San Juan,
Colombia; and in the Rio-Goascoran, along the border between El
Salvador and Honduras.
In its Atlantic distribution it is commonly found in freshwater
rivers and lakes. It is noted for running far upstream in freshwater and
has been recorded at least 1,340 km from the ocean in the Amazon
(Manacapuru, Brazil); in Lake Nicaragua and the San Juan and other
various east coast rivers of Nicaragua; Lake Yzabal and Rio Dulce,
Guatemala; Rio San Juan and Magdalena River, Colombia; Mali or
Senegal in the Faleme River; Saloum River of Senegal; Gambia; and
the Ceba River of Guinea-Bissau.
The largetooth sawfish is an adept predator feeding on a variety
of small bony fishes, which it stuns with its saw before consuming,
and animals (fish and invertebrates) it stirs from the substrate.
It is ovoviviparous giving birth to 1-11 fully developed young
per litter with 7-9 young being the most common litter sizes. Size
at birth is about 76 cm (TL) [Nicaraguan specimens]. In Lake
Nicaraguan stocks the breeding season has been reported to be in
early June and sometimes into July. After a five month gestation,
young are born from early October to perhaps early December. Size
at sexual maturity for both males and females is 2.4-3.0 m, at ten years
of age (Thorson 1982). Maximum adult size is at least 5.7 m (TL) and
possibly to 6.1 m (TL). It attains a maximum weight of at least 600 kg.
Lifespan in the wild is unknown; Thorson (1982) suggests 30 years.
Conservation status
This species has been fished intensively at various locations within its
range, with dramatic declines in local stocks noted as a result. In Lake
Nicaragua (Central America) Thorson noted large catches during his
preliminary visits to Granada in 1963 (T.B. Thorson, personal
communication). However, intense efforts for both this species and
the bull shark, Carcarhinus leucas, which occurred sympatrically in
the lake led to rapid decline of stocks. Taniuchi (1992) did not see any
sawfish or sharks in the lake during his survey of Central American
freshwater elasmobranchs. He noted that during the entire previous
season only one of each species had been reported in the fishery.
The fisheries for this
species have been characterised by
continued effort long after
local stocks are completely
decimated. Because of the long
tooth-studded saw, all sawfish species
are disproportionately subject to incidental
capture in net gear set for other species in both
marine and freshwater environments.
Products recovered from this species are typical of
those for other species of sawfishes and include dried saws for
curios (primary product), meat for human consumption, and to a
lesser degree hides for leather. It is unknown if useable fins are
recovered for the shark fin trade. Since stocks of the largetooth
sawfish in Central America were fished down well before the current
surge in interest in shark fins in the mid 1980s, the impact that practice
might have had is indeterminable. However, the authors saw other
batoids (i.e., Rhina ancylostoma, [bowmouth guitarfish] and two
species of Rhynchobatus [white-spotted guitarfish]) in the markets of
Thailand [December 1993] that had been trimmed of fins for the market.
Recent collection of seven specimens of a closely-related species
(P. microdon, Australia) for public aquarial display raises concern.
Sawfishes, in general, tend to be of low to moderate abundance in
freshwater habitats. Zealous collectien efforts, even in the name of
research, may seriously compromise a stressed reproductive
population.
Selected bibliography
Bigelow, H.B., and Schroeder, W.C. 1953. Sawfishes, guitarfishes,
skates, and rays. Chimaeras. Fishes of the Western North Atlantic.
Memoirs of the Sears Memorial Foundation for Marine Research
1(2): 1-514.
Compagno, L.J.V., and Cook, S.F. In Press. The exploitation and
conservation of freshwater elasmobranchs: status of taxa and
prospects for the future. [Journal of Aquaculture and Aquatic
Science (USA)].
Taniuchi, T. 1992. Report on preliminary investigation of freshwater
elasmobranchs in Mexico and Central America. Report of Japanese
Society for Elasmobranch Studies 29: 33-49. [Japanese with
English abstract].
Thorson, T. B. 1982. Life history implications of a tagging study
Of the large-tooth sawfish, Pristis perotteti, in the Lake Nicaragua-
Rio San Juan System. Environ. Biol. Fishes, 7(3): 207-228.
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